From NASA-Update #13
Fri, 23 Sep 2011 11:55:17 PM CDT
"As of 10:30 p.m. EDT on Sept. 23, 2011, the orbit of UARS was 85 miles by 90 miles (135 km by 140 km). Re-entry was expected between 11:45 p.m. Friday, Sept. 23, and 12:45 a.m., Sept. 24, Eastern Daylight Time (3:45 a.m. to 4:45 a.m. GMT). During that time period, the satellite was passing over Canada and Africa, as well as vast areas of the Pacific, Atlantic and Indian oceans. The risk to public safety was very remote. NASA is working to confirm the re-entry location and time and will provide an update shortly."
"LAST SIGHTINGS OF UARS? Observers in central Texas saw UARS streaking overhead (but not disintegrating) at 8:18 PM CDT on Sept. 23rd. It was spotted again over western Colorado at ~9:46 pm CDT ("Still intact, but tumbling," says observer Scott Sheriff) and again over Minnesota at 9:55 pm CDT. Since then, however, no observers have reported seeing the doomed satellite. NASA's estimated window for re-entry (between 11:45 p.m. Sept. 23 and 12:45 a.m. Sept. 24 EDT) has passed, so UARS might be no more."
Crashed near Calgary?
"A six-tones NASA science satellite plunged through the atmosphere early on Saturday, breaking up and possibly scattering debris in Canada, NASA said."
Sat, 24 Sep 2011 02:16:50 AM CDT
"NASA's decommissioned Upper Atmosphere Research Satellite fell back to Earth between 11:23 p.m. EDT Friday, Sept. 23 and 1:09 a.m. EDT Sept. 24. The satellite was passing eastward over Canada and Africa as well as vast portions of the Pacific, Atlantic and Indian oceans during that period. The precise re-entry time and location are not yet known with certainty."
NASA now says the falling UARS satellite will likely tumble to earth sometime late Friday night into early Saturday morning. The slower descent means the satellite will pass over North America and Europe several times during that time.
Track the UARS orbit here.
There is a small chance, but still a chance that some of the debris could come down over the USA. Here's the latest from NASA Friday:
Fri, 23 Sep 2011 09:45:08 AM CDT
"As of 10:30 a.m. EDT on Sept. 23, 2011, the orbit of UARS was 100 miles by 105 miles (160 km by 170 km). Re-entry is expected late Friday, Sept. 23, or early Saturday, Sept. 24, Eastern Daylight Time. Solar activity is no longer the major factor in the satellite's rate of descent. The satellite's orientation or configuration apparently has changed, and that is now slowing its descent. There is a low probability any debris that survives re-entry will land in the United States, but the possibility cannot be discounted because of this changing rate of descent. It is still too early to predict the time and location of re-entry with any certainty, but predictions will become more refined in the next 12 to 18 hours."
It's the biggest thing since Skylab, and it's going to put on a show Friday.
It's called UARS (Upper Atmosphere Research Satellite) and will break up and reenter earth's atmosphere Friday afternoon EDT according to NASA.
"The Upper Atmosphere Research Satellite (UARS) is an orbital observatory whose mission is to study the Earth's atmosphere, particularly the protective ozone layer. It is 35 feet long, 15 feet in diameter, weighs 13,000 pounds, and carries 10 instruments. UARS orbits at an altitude of 375 miles with an orbital inclination of 57 degrees. Designed to operate for three years, six of its ten instruments are still functioning. UARS measures ozone and chemical compounds found in the ozone layer which affect ozone chemistry and processes. UARS also measures winds and temperatures in the stratosphere as well as the energy input from the Sun."
UARS will come down in pieces according to NASA.
45-80km "burn up altitude"
150 pieces burning up
26 pieces "reentering" (crashing to earth!)
500 mile long potential debris field
1 in 3,200 odds that any human will be hit by falling debris
1 in several trillion; odds you'll be hit!
So where will it land?
You can track the UARS orbit here.
NASA says the satellite likely won't be orbiting over North America when it breaks up. But where the pieces will land is anybody's guess, and there are many variables.
Here's a great layout of the break up courtesy of the Washington Post:
(Click image to enlarge)
A nice animation here of the potential break up from space.com
As we used to say on Jet Streaming; "Keep ypur weather eye to the sky" Friday!
"Southern Lights" Dazzle:
Speaking of NASA and flying objects, check out this amazing video of the "Aurora Australias" or southern lights as the Space Shuttle flies over the Indian Ocean last Saturday!
Cut-off low hangs tough:
"A cut-off low is a weatherman's woe."
The persistent October-like low pressure system is in no hurry to move on this week.
Minnesota reamins on the back side of a swirling cold pool. Clouds with the system have been hanging tough in eastern Minnesota, while the sun is shining in the west.
The low is in no hurry to move east. Cut offs are notorious for sitting and spinning in spite of forecast models best attempts to push them east.
The result is persistence. Look for another cool day Friday, with the trend for more sun as we head into the weekend. The warm up will be slow. Expect highs only in the 60s this weekend.
This will be a classic "football weather" weekend. It will also be a great weekend to get those early fall yard chores done. Where's that "to do" list anyway?